Phase III Specific Aims: The specific aims of the randomized portion of the CRYO-ROP follow-up study are to address the following questions: I. Are there long-term structural or functional ocular sequelae in eyes with Threshold ROP that are treated with cryotherapy (vs. those that are not treated) that would require re-evaluation of the risk/benefit ratio of recommending cryotherapy? 2. Do the study data suggest that the "threshold" for cryotherapy should be lowered? Yearly eye examinations will be performed at 7, 8, 9, and 10 years of age in the randomized ROP patients. The specific aims of the Natural History portion of the CRYO-ROP follow- up study involve only those CRYO-ROP children who did not develop ROP as an infant. Examinations will be performed at 7, 9, and 10 years of age in these study patients and data collection is designed to address the same ocular status question as the Phase III study of randomized patients.